The researchers at Houston’s Rice University have found a unique behavior of lithium atoms. We are well familiar with the common disappearing act by any magician. Similarly, a new experiment by the scientists have found that the Lithium atoms can also disappear when chilled to near absolute zero temperatures as they have the ability to pass through other particles of matter.
The scientists performed a experiment using Bose Einstein condensates (BECs), a state of matter that forms near absolute zero temperatures.
A “matter wave” of energy is created with the merging of atoms into the one quantum mechanical unit, as the team discovered that when they subjected lithium atoms to highly cold temperatures.
Thousands of lithium atoms were chilled by the researchers to one-millionth of a degree of absolute zero that led to the creation of a BEC state called a soliton.
During the soliton formation, the atoms witnessed balanced quantum pressure that exhibited attractive forces while being pushed apart. This quality allowed them to pass through each other without being in the same spot.
Lead study author Randy Hulet said, “It happens because of the interference by the ‘wave packet’. Think of them as waves that can have a positive or negative amplitude. One of the solitons is positive, while the other is negative. Hence, they cancel each other. The probability of them being in the spot where they meet is zero. They pass through the spot, but they can’t be seen there.”
Each BEC was created individually and then separated the center with a light sheet to develop a soliton. After the sheet was removed, the solitons happened to pass through each other but never occupied the same location.
The researchers conducted thousands of soliton collisions that yielded mixed results. During the collision, some of the solitons passed through each other while rest of the solitons bounced back of their counterparts. The variation between two groups of the solitons can be explained by their phase of the waves, which is uncontrollable.
Hulet said, “In the out-of-phase case, the one with the gap, where it appeared that they had been bouncing off of each other, we still saw the gap but we also saw the larger soliton emerge unfazed on the other side of the gap. In other words, it jumped through the gap.”
The findings of the study were published in the journal Nature Physics.